<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        .container {
            width: 1200px;
            margin: 0 auto;
        }
        .box {
            box-sizing:border-box; /* 盒模型设置为怪异（IE）盒模型 */
            margin: 0 10px;
            border: 1px solid black;
            padding: 5px;
            display: inline-block;/* 天坑 有间隙 */
            width: 50%;
            width: 580px;
            height: 100px;
            background-color: green;
        }
        .box:nth-child(2) {
            background-color: yellow;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="box">1</div><div class="box">2</div>
    </div>
</body>
</html>